Samplers for extracting equal volume samples from flowing streams are well known in the art. For example, a sampling connection may be made in a pipeline to extract several samples over time to represent the "average" contents of the stream over a given period. Those samples flow into a storage container from which representative samples may be taken for analytical tests of the materials. The results of the analytical tests are taken as the representation of the contents which have flowed past the test point in the pipeline over a given time.
Some samplers take samples more or less frequently or larger or smaller samples, both proportional to pipeline flow rates. Other systems simply take timed or periodic samples of the same size. Whatever the frequency or size of samples taken, a record of the size of the sample is necessary. Equally important is the maintenance of sample integrity in the case of the presence of volatile constituents in the sample. Another important aspect is the representative accuracy of the composite sample to be analyzed, given that varying individual sample numbers and sizes of individual samples may be taken in the period in question.